SNHG17, as an EMT-related lncRNA, promotes the expression of c-Myc by binding to c-Jun in esophageal squamous cell carcinoma

The essential roles of lncRNAs/PI3K/AKT axis in gastrointestinal tumors

The role of long noncoding RNA (lncRNA) in tumors, particularly in gastrointestinal tumors, has gained significant attention. Accumulating evidence underscores the interaction between various lncRNAs and diverse molecular pathways involved in cancer progression. One such pivotal pathway is the PI3K/AKT pathway, which serves as a crucial intracellular mechanism maintaining the balance among various cellular physiological processes for normal cell growth and survival. Frequent dysregulation of the PI3K/AKT pathway in cancer, along with aberrant activation, plays a critical role in driving tumorigenesis. LncRNAs modulate the PI3K/AKT signaling pathway through diverse mechanisms, primarily by acting as competing endogenous RNA to regulate miRNA expression and associated genes. This interaction significantly influences fundamental biological behaviors such as cell proliferation, metastasis, and drug resistance. Abnormal expression of numerous lncRNAs in gastrointestinal tumors often correlates with clinical outcomes and pathological features in patients with cancer. Additionally, these lncRNAs influence the sensitivity of tumor cells to chemotherapy in multiple types of gastrointestinal tumors through the abnormal activation of the PI3K/AKT pathway. These findings provide valuable insights into the mechanisms underlying gastrointestinal tumors and potential therapeutic targets. However, gastrointestinal tumors remain a significant global health concern, with increasing incidence and mortality rates of gastrointestinal tumors over recent decades. This review provides a comprehensive summary of the latest research on the interactions of lncRNA and the PI3K/AKT pathway in gastrointestinal tumor development. Additionally, it focuses on the functions of lncRNAs and the PI3K/AKT pathway in carcinogenesis, exploring expression profiles, clinicopathological characteristics, interaction mechanisms with the PI3K/AKT pathway, and potential clinical applications.

Roles of long non‑coding RNAs in esophageal cell squamous carcinoma (Review)

Esophageal squamous cell carcinoma (ESCC) is a prevalent and deadly malignancy of the digestive tract. Recent research has identified long non‑coding RNAs (lncRNAs) as crucial regulators in the pathogenesis of ESCC. These lncRNAs, typically exceeding 200 nucleotides, modulate gene expression through various mechanisms, including the competing endogenous RNA (ceRNA) pathway and RNA‑protein interactions. The current study reviews the multifaceted roles of lncRNAs in ESCC, highlighting their involvement in processes such as proliferation, migration, invasion, epithelial‑mesenchymal transition, cell cycle progression, resistance to radiotherapy and chemotherapy, glycolysis, apoptosis, angiogenesis, autophagy, tumor growth, metastasis and the maintenance of cancer stem cells. Specific lncRNAs like HLA complex P5, LINC00963 and non‑coding repressor of NFAT have been shown to enhance resistance to radio‑ and chemotherapy by modulating pathways such as AKT signaling and microRNA interaction, which promote cell survival and proliferation under therapeutic stress. Furthermore, lncRNAs like family with sequence similarity 83, member A antisense RNA 1, zinc finger NFX1‑type containing 1 antisense RNA 1 and taurine upregulated gene 1 are implicated in enhancing invasive and proliferative capabilities of ESCC cells through the ceRNA mechanism, while interactions with RNA‑binding proteins further influence cancer cell behavior. The comprehensive analysis underscores the potential of lncRNAs as biomarkers for prognosis and therapeutic targets in ESCC, suggesting avenues for future research focused on elucidating the detailed molecular mechanisms and clinical applications of lncRNAs in ESCC management.

Functional role of lncRNAs in gastrointestinal malignancies: the peculiar case of small nucleolar RNA host gene family

Long noncoding RNAs (lncRNAs) play crucial roles in normal physiology and are often de-regulated in disease states such as cancer. Recently, a class of lncRNAs referred to as the small nucleolar RNA host gene (SNHG) family have emerged as important players in tumourigenesis. Here, we discuss new findings describing the role of SNHGs in gastrointestinal tumours and summarize the three main functions by which these lncRNAs promote carcinogenesis, namely: competing with endogenous RNAs, modulating protein function, and regulating epigenetic marking. Furthermore, we discuss how SNHGs participate in different hallmarks of cancer, and how this class of lncRNAs may serve as potential biomarkers in cancer diagnosis and therapy.

Targeting epigenetic deregulations for the management of esophageal carcinoma: recent advances and emerging approaches

Ranking from seventh in incidence to sixth in mortality, esophageal carcinoma is considered a severe malignancy of food pipe. Later-stage diagnosis, drug resistance, and a high mortality rate contribute to its lethality. Esophageal squamous cell carcinoma and esophageal adenocarcinoma are the two main histological subtypes of esophageal carcinoma, with squamous cell carcinoma alone accounting for more than eighty percent of its cases. While genetic anomalies are well known in esophageal cancer, accountability of epigenetic deregulations is also being explored for the recent two decades. DNA methylation, histone modifications, and functional non-coding RNAs are the crucial epigenetic players involved in the modulation of different malignancies, including esophageal carcinoma. Targeting these epigenetic aberrations will provide new insights into the development of biomarker tools for risk stratification, early diagnosis, and effective therapeutic intervention. This review discusses different epigenetic alterations, emphasizing the most significant developments in esophageal cancer epigenetics and their potential implication for the detection, prognosis, and treatment of esophageal carcinoma. Further, the preclinical and clinical status of various epigenetic drugs has also been reviewed.

Long non-coding RNA AC245100.4 activates the PI3K/AKT pathway to promote PCa cell proliferation by elevating PAR2

Background

Prostate cancer (PCa) is among the most generally diagnosed cancers in males. A long non-coding RNA (lncRNA) called AC245100.4 has been discovered and linked to PCa carcinogenesis. However, its specific and potential mechanism is uncertain in PCa. In this research, we investigated the role of AC245100.4 in cell proliferation and the underlying mechanism in PCa cells.

Methods

qRT-PCR assays were utilized to detect AC245100.4 expression and confirm its downstream target. The pathways related to AC245100.4 were identified by RAP-MS. PCa cell proliferation was experimented by Cell Counting Kit-8 and Colony formation assays. Western blot was performed to detect PAR2, AKT, p-AKT, Cyclin D1 and PCNA expression.

Results

AC245100.4/PAR2 overexpression promotes PCa cell proliferation and the opposite results are obtained after AC245100.4/PAR2 knockdown. Mechanistically, we found that PAR2 is confirmed as the AC245100.4 downstream target and AC245100.4 promotes PCa cell proliferation by regulating PAR2. AC245100.4 promotes PCa cell proliferation via PI3K/AKT pathway. Rescue assays validated that PAR2 knockdown reversed the impact of AC245100.4 overexpression on increasing p-AKT protein levels.

Conclusion

This research revealed that AC245100.4 enhances cell proliferation in PCa cells through modulating the PAR2/PI3K/AKT axis, which may offer novel tumor markers and potential therapeutic targets for PCa.

Lactobacillus rhamnosus GG ameliorates radiation-induced lung fibrosis via lncRNASNHG17/PTBP1/NICD axis modulation

Radiation-induced pulmonary fibrosis (RIPF) is a major side effect experienced for patients with thoracic cancers after radiotherapy. RIPF is poor prognosis and limited therapeutic options available in clinic. Lactobacillus rhamnosus GG (LGG) is advantaged and widely used for health promotion. However. Whether LGG is applicable for prevention of RIPF and relative underlying mechanism is poorly understood. Here, we reported a unique comprehensive analysis of the impact of LGG and its' derived lncRNA SNHG17 on radiation-induced epithelial-mesenchymal transition (EMT) in vitro and RIPF in vivo. As revealed by high-throughput sequencing, SNHG17 expression was decreased by LGG treatment in A549 cells post radiation and markedly attenuated the radiation-induced EMT progression (p < 0.01). SNHG17 overexpression correlated with poor overall survival in patients with lung cancer. Mechanistically, SNHG17 can stabilize PTBP1 expression through binding to its 3'UTR, whereas the activated PTBP1 can bind with the NICD part of Notch1 to upregulate Notch1 expression and aggravated EMT and lung fibrosis post radiation. However, SNHG17 knockdown inhibited PTBP1 and Notch1 expression and produced the opposite results. Notably, A549 cells treated with LGG also promoted cell apoptosis and increased cell G2/M arrest post radiation. Mice of RIPF treated with LGG decreased SNHG17 expression and attenuated lung fibrosis. Altogether, these data reveal that modulation of radiation-induced EMT and lung fibrosis by treatment with LGG associates with a decrease in SNHG17 expression and the inhibition of SNHG17/PTBP1/Nothch1 axis. Collectively, our results indicate that LGG exerts protective effects in RIPF and SNHG17 holds a potential marker of RIPF recovery in patients with thoracic cancers.

Integrative pan-cancer analysis indicates the prognostic importance of long noncoding RNA SNHG17 in human cancers

BACKGROUND

Cancer is one of the most widespread causes of death today. Early diagnosis can dramatically reduce cancer-related mortality. Studies have shown that the lncRNA Small Nucleolar RNA Host Gene 17 (SNHG17) is aberrantly expressed in various types of solid tumors. Nevertheless, its prognostic value remains to be elucidated. The main objective of this meta-analysis was to elucidate whether SNHG17 can be considered as a potential prognostic biomarker for a variety of cancers.

METHODS

Correlational studies were screened from Cochrane, Embase, PubMed, and Web of Science. Hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were pooled, and the role of SNHG17 in cancer was analyzed. The Cancer Genome Atlas (TCGA) database was employed to verify the results.

RESULTS

Seventeen original papers including 1451 patients were included in the meta-analysis. SNHG17 expression was upregulated in various cancers. Overexpression of SNHG17 was significantly correlated with worse overall survival (OS) (HR = 1.92, 95% CI 1.55-2.37, P < 0.001) and relapse-free survival (RFS) (HR = 1.87, 95% CI 1.06-3.30, P = 0.030). Furthermore, overexpression of SNHG17 was predictive of earlier lymph node metastasis (LNM) (OR = 2.94, 95% CI 2.29-3.78, P < 0.001), more advanced tumor-node-metastases (TNM) stage (OR = 3.56, 95% CI 2.22-5.68, P < 0.001), larger tumor size (OR = 2.18, 95% CI 1.65-2.88, P < 0.001), worse differentiation grade (OR = 1.69, 95% CI 1.26-2.25, P < 0.001), and earlier distant metastasis (DM) (OR = 1.63, 95% CI 1.03-2.56, P = 0.033) in human cancers. Moreover, further inquiry based on TCGA dataset validated that SNHG17 was high expression in various tumors and foresaw unfavorable clinical prognosis.

CONCLUSIONS

Overexpression of SNHG17 correlates with poor prognosis and advanced clinicopathological features in cancer patients and may be a potential prognostic indicator and a therapeutic target for cancer treatment.

Prognostic Profiling of the EMT-Associated and Immunity-Related LncRNAs in Lung Squamous Cell Carcinomas

Lung squamous cell carcinoma (Lung SCC) is associated with metastatic disease, resulting in poor clinical prognosis and a low survival rate. The aberrant epithelial–mesenchymal transition (EMT) and long non-coding RNA (LncRNA) are critical attributors to tumor metastasis and invasiveness in Lung SCC. The present study divided lncRNAs into two subtypes, C1 and C2 (Cluster 1 and Cluster 2), according to the correlation of EMT activity within the public TCGA and GEO databases. Subsequently, the differential clinical characteristics, mutations, molecular pathways and immune cell deconvolution between C1 and C2 were evaluated. Lastly, we further identified three key lncRNAs (DNM3OS, MAGI2-AS3 and LINC01094) that were associated with EMT and, at the same time, prognostic for the clinical outcomes of Lung SCC patients. Our study may provide a new paradigm of metastasis-associated biomarkers for predicting the prognosis of Lung SCC.

Enabling factor for cancer hallmark acquisition: Small nucleolar RNA host gene 17

The role of long non-coding RNA (lncRNA) in human tumors has gradually received increasing attention in recent years. Particularly, the different functions of lncRNAs in different subcellular localizations have been widely investigated. The upregulation of lncRNA small nucleolar RNA host gene 17 (SNHG17) has been observed in various human tumors. Growing evidence has proved that SNHG17 plays a tumor-promoting role in tumorigenesis and development. This paper describes the molecular mechanisms by which SNHG17 contributes to tumor formation and development. The different functions of SNHG17 in various subcellular localizations are also emphasized: its function in the cytoplasm as a competing endogenous RNA (ceRNA), its action in the nucleus as a transcriptional coactivator, and its function through the polycomb repressive complex 2 (PRC2)-dependent epigenetic modifications that regulate transcriptional processes. Finally, the correlation between SNHG17 and human tumors is summarized. Its potential as a novel prognostic and diagnostic biomarker for cancer is explored especially.

C-Myc Expression in Oral Squamous Cell Carcinoma: Molecular Mechanisms in Cell Survival and Cancer Progression

Oral squamous cell carcinoma (OSCC) represents 90% of malignant epithelial cancer that occurs in the oral cavity. The c-Myc factor is expressed in multiple types of cancer, comprising head and neck squamous cell carcinoma (HNSCC), where it plays a fundamental role in tumor prognosis and in the self-renewal of tumor stem cells. However, the role of c-Myc in controlling OSCC cells is not well-known. The aim of the present study is the evaluation of the biological roles and regulatory mechanism of c-Myc in the pathogenesis of OSCC. Results indicated that c-Myc, c-Jun, Bcl-2, hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), ERK 1/2 and pERK1/2 were overexpressed in a cellular model of squamous cell carcinoma, Cal-27. Doxorubicin (Doxo), a common chemotherapeutic agent, inhibited cell invasion, hypoxia, angiogenesis and inflammation in a cellular model of Cal-27 cells as indicated by downregulation of MMP-9, VEGF, ERK 1/2 and pERK 1/2 as well as promoted apoptosis as evidenced by the downregulation of Bcl-2 protein. This work aimed at underlying the functional relevance of c-Myc in OSCC and the HIF-Myc collaboration by integrating the knowledge on this molecular link in an OSCC tumor microenvironment. The results obtained showed for the first time the vital role of c-Myc in Cal-27 in cell survival/proliferation and tumor growth as well as the negative regulatory effect of Doxo against c-Myc signaling pathway.